The present invention generally relates to a novel concentrate containing complexed iodine. More particularly, the present invention relates to an iodine complex concentrate for use in antimicrobial use compositions.
Iodine compositions have long been known to impart desirable antimicrobial and non-staining characteristics. Complexed iodine compositions are known to be useful as sanitizers for elements ranging from contact surfaces and glassware to plant formulation facilities. An especially important application for iodine compositions is in clean-in-place (CIP) systems. CIP systems are generally found in industries which produce fluidized ingestible products for humans or animals such as the dairy industry, the pharmaceutical industry, and the food industry. Clean-in-place systems are generally regarded as large production plant systems having reservoirs, pipes, pumps and mixing vessels which cannot be broken down to be cleaned. Additionally, clean-in-place preparation systems often require high sanitization when used in the production of ingestible substances.
In order to be dependable and useful to an end user, iodine compositions must be stable (i.e. remain homogeneous) over a wide range of temperature and prolonged periods of time. If stability is lost, and the products separate, the utility of the composition is significantly degraded and they can present a potential hazard to the user. Generally speaking, stability in this context means that a given product must remain completely homogeneous after extended storage at temperatures ranging from room temperature to as high as 40xc2x0 C., which can occur during transport in closed vehicles. Furthermore, although a given product may separate when frozen, especially after undergoing several freeze-thaw cycles, it must be readily reconstitutable as a homogeneous mixture upon simple shaking or mixing.
Iodine-based antimicrobial use products designed for topical application to the skin are normally formulated with a certain amount of emollient. The most common emollients employed are glycerin, lanolin and its derivatives, sorbitol, fatty acid esters of polyhydroxylated compounds and propylene glycol. These emollients are used at levels ranging from below 1% to as much as 10% in use compositions. Glycerin is the most widely used emollient in bovine teat dips and is also used extensively at low levels in human topical detergent-iodine and povidone-iodine formulations. Emollients are needed because of the harshness to skin associated with those surfactants contained in the detergent part of the composition.
Another desirable functional charactersitic for iodine-based antimicrobial use compositions designed for topical application is the ability to spread evenly on the skin and not drain off so rapidly as to prevent insufficient germicidal contact time. Many of the usual ingredients in antimicrobial products contribute to viscosity. However, it is common for topical products to be formulated with a specific thickener to provide added viscosity. There are many viscosity modifiers compatible with iodine-based antimicrobial use systems, such as carboxymethylcellulose derivatives, polyacrylate derivatives, alginates, xanthates and polysaccharides. These are typically used at levels below 1% by weight in a final use composition. These types of ingredients, properly selected, have an insignificant effect on the homogeneity of a given use composition. On the other hand, where dilutable concentrates are desired, viscosity-modifying additives can become a problem and special care must be taken in the selection of specific agents and their levels of use in concentrates.
The prior art is replete with examples of antimicrobial use formulations having relatively high detergent/average available iodine ratios in excess of 5:1. There are, however, a number of potential advantages associated with the use of very low detergent/average available iodine ratios in germicidal iodine concentrates and use compositions designed for skin or tissue application. For example, in a low ratio product of this type, there would be less organic matter to react with the iodine, thereby rendering such compositions more stable relative to the normal high ratio of detergent to average available iodine content. Another advantage is that reduced amounts of detergent would be expected to be less irritating to the skin and would accordingly require a lesser amount of emollient. Compositions with lower detergent/average available iodine ratios could be formulated to have higher, and more stable, free or uncomplexed iodine levels. The use of minimal amounts of detergent also would allow for the possibility of reduced water content in concentrates, thereby correspondingly reducing packaging, shipment and storage costs. However, one obvious disadvantage associated with these types of formulations is that lower amounts of detergent component reduce the detersive effectiveness of the germicidal composition. Moreover, the use of lower ratios of detergent/average available iodine also results in the composition becoming less storage stable which makes them significantly less marketable.
Accordingly, it is an object of the present invention to provide iodine complex concentrate designed for topical applications onto both human and animal skin that employs a component acting as both a complexing agent for the iodine, and a mild yet effectively detersive surfactant which is less harsh on skin and tissue, thereby requiring the addition of little if any emollients to the antimicrobial use composition.
It is another object of the present invention to provide an iodine complex concentrate for use in antimicrobial use compositions to disinfect and sanitize various contact surfaces including those present in CIP systems, as well as glassware which is capable of being employed at relativley high detergent/average available iodine ratios, thus making the formulated antimicrobial compositions more storage stable over prolonged time periods and temperature ranges while imparting maximum detersive properties.
The present invention overcomes the problems outlined above by providing a stable iodine complex concentrate for use in various aqueous antimicrobial use compositions. Accordingly, the present invention provides an iodine complex concentrate containing:
(a) from about 0.5 to about 30% by weight of iodine;
(b) from about 0.2 to about 14% by weight of a component selected from the group consisting of iodide salt, iodide acid and mixtures thereof; and
(c) from about 2.0 to about 85% by weight of a nonionic sugar surfactant selected from the group consisting of alkyl glucose esters, aldobionamides, gluconamides, glyceramides, glyceroglycolipids, polyhydroxy fatty acid amides, alkyl polyglycosides having the general formula I:
R1O(R2O)b(Z)axe2x80x83xe2x80x83I
wherein R1 is a monovalent organic radical having from about 6 to about 30 carbon atoms; R2 is divalent alkylene radical having from 2 to 4 carbon atoms; Z is a saccharide residue having 5 or 6 carbon atoms; b is a number having a value from 0 to about 12; a is a number having a value from 1 to about 6, and mixtures thereof, all weights being based on the weight of the concentrate.
The present invention also provides an aqueous antimicrobial use composition containing the above-disclosed iodine complex concentrate and a diluent.
The present invention also provides a process for cleaning, disinfecting and sanitizing an intended surface involving contacting the intended surface with the above-disclosed aqueous antimicrobial use composition.